<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>比较含退格的字符串</title>
</head>
<body>
  <script>
    function fn(S, T) {
      var c = (s, a = []) => {
        for (var i = 0; i < s.length; i++)
          s[i] === '#' ? a.pop() : a.push(s[i])
        return a.join('')
      }
      return c(S) === c(T)
    }
    console.log(fn('ab#c', 'ad#c'))
  </script>
</body>
</html>